X-ray systems are routinely used for screening vehicles and cargo crossing international borders, as well as for screening passengers and baggage. Such systems are based on the interaction of penetrating radiation with contents of a vehicle or a cargo enclosure. Current systems allow a human operator to view the contents of a vehicle on a display and flag any anomalies. Manual inspection of X-ray images makes this a slow process. Due to the large number of vehicles crossing international borders there is a pressing need for developing systems and methods that can assist the operator in screening vehicles.
One modality of X-ray inspection that has proven highly efficacious in a multitude of circumstances is that of scatter imaging, or, more particularly, backscatter imaging. One backscatter imaging system, in the context of which the present invention may be advantageously applied, is fully described in U.S. Pat. No. 7,400,701 (to Cason), issued Jul. 15, 2008, and incorporated herein by reference.